Acumen Pharmaceuticals, Inc. - Common Stock, $0.0001 par value per share (ABOS)

CUSIP: 00509G209

Q1 2026 13F Holders as of 31 Mar 2026

Security identity 2 facts
Security type / class
Equity / Common Stock, $0.0001 par value per share
Shares outstanding
72,227,200
Holder snapshot 9 facts
Total 13F shares
46,001,051
Share change
+10,282,919
Total reported value
$108,541,469
Put/Call ratio
109%
Reported price per share
$2.36
Number of holders
84
Value change
+$24,478,369
Number of buys
50
Number of sells
17

Security key

00509G209

Report period

Q1 2026

Institutions

84

Top holders

10

ABOS full security history Ownership snapshot Full 13F holder table Previous quarter: Q4 2025 Acumen Pharmaceuticals, Inc. SEC filings Acumen Pharmaceuticals, Inc. company facts

Broader feeds

Latest 13F filings Latest 13D/G filings Investors directory

Ownership snapshot

Top reported holders of ABOS - Acumen Pharmaceuticals, Inc. - Common Stock, $0.0001 par value per share (13F + 13D/G + 3/4/5)

Grouped by holder across the latest SEC ownership disclosures. Start with comparable ownership when available, then verify the linked 13F, 13D/G, or 3/4/5 evidence.

Lead holder
RA CAPITAL MANAGEMENT, L.P.
13D/G signal
RA CAPITAL MANAGEMENT, L.P.
Evidence rows
15
Latest as of
13 Mar 2026
13D/G 3/4/5 13F Lead comparable stake: 30% 13D/G row: RA CAPITAL MANAGEMENT, L.P. Showing 1-6 of 15 holder rows.
Holder Evidence Ownership % Position 12M Net Δ As of
RA CAPITAL MANAGEMENT, L.P.
13D/G 3/4/5 13F
Director, 10%+ Owner · Company
13D/G 3/4/5 13F
30%
$55,075,356
21,101,669 shares
 +$15,883,432 13 Mar 2026
Sands Capital Alternatives, LLC
13F 13D/G
Company
13F 13D/G
5.6%
from 13D/G
$7,210,028
3,417,075 shares
 — 31 Dec 2025
James B. Murray Jr.
13D/G
13D/G
5%
$9,425,650
3,611,360 shares
 $0 04 Apr 2025
FRANKLIN RESOURCES INC
13F 13D/G
Company
13F 13D/G
3.8%
from 13D/G
$4,863,753
2,305,096 shares
 — 31 Dec 2025
FMR LLC
13F
Company
13F
2.8%
$4,278,019
2,027,497 shares
 — 31 Dec 2025
VANGUARD GROUP INC
13F
Company
13F
2.3%
$3,489,459
1,653,772 shares
 — 31 Dec 2025
How to read this table

Rows are grouped by holder and ranked first by SEC-reported ownership % when it is safely comparable, then by disclosed holdings value. — indicates unavailable or non-comparable values; "mixed-class rows" means the latest filing spans non-comparable classes.

13F holder rows

Institutional holders as of Q1 2026

Investor-level positions for this CUSIP, loaded as an interactive table.

Institutions
84
Shares
46,001,051
Rows available
84
Investor Option Weight % Change % Reported value * Price Shares Share Change Activity Report Period

* Reported price is the security price as of the portfolio date and can indicate the last known price at which the security was still held. The marker flags a reported price that failed the local validity check.

Compare Q1 2026 vs Q4 2025 Across Filers

Q4 2025 holders
70
Q1 2026 holders
84
Holder diff
14
Investor Q4 2025 Shares Q1 2026 Shares Share Diff Share Chg % Q4 2025 value Q1 2026 value Value change Value Chg %

Trend: ostatnie 8 kwartałów (+ wybrane okresy porównania).

Quarterly Holders Trend
Quarterly Value Trend
Quarterly Shares Trend
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